There are multiple ways to do that. You can store user email address in Account form in a field. When User lookup value gets changed at account, then update that field on account form using real time workflows.

1. On the Account form, create a field to capture the User's email address

2. Configure a Real-Time workflow on the Account form to populate the User's email address to this field.

3. Create a new field on the Opportunity form to capture the user's email address. Ensure the datatype and length of this field is the same as the one created on the Account entity

Open the relationship between Opportunity and Account [Potential Customer] and create a new mapping between the Opportunity User Email field and the Account User Email field.

The other option is to replace Step (3) above with a real-time workflow which runs upon create of the Opportunity record.This workflow will populate the Account [User Email] value to the Opportunity [User Email] field.

My suggestion you use a web resources to display User infor, including fullname, email, business unit, etc since Quick View Form only supports up to 1 level.

Because, if not, if you store the information at somewhere, let's say Account or Opportunity, you should maintain this.

For example: if the lookup field to user in the Account form has been changed, then should change the field at the Opportunity form level.

Then, if you store in the Account as well, you should maintain when create and update as well.

It is up to you.

If you don't want to use web resources, then, the easier way is by creating a workflow, set to Account, triggered once created and updated (if User lookup field in Account form updated), then update copy over the required fields from User to Account.

Then, assuming, you have all those required fields, you stored in the Account.

Thus, you can use creating a new Quick View Form of Account, then put in the Opportunity Form.

This is the sample of quick view form:

*assuming this is in the Opportunity Form, and the email is User email stored in the Account.

Using this method, you will only need to maintain fields in the Account once the lookup field to the User at the Account entity was updated.

If I run a realtime workflow, am I able to pull data for all records from the parent record to the child record?

--> Yes, you can, pull data from parent to the child record, by creating fields with the same data type.

I read somewhere that the workflow can only process 300 records at a time, is that correct? --> Basically Out Of The Box only afford until 250 records, but this is for on demand workflow (because you select the records from view, which is, maximum is 250 records out of the box, then click the Run Workflow ribbon), but in this case you are using real time workflow and not on demand workflow.

"I read somewhere that the workflow can only process 300 records at a time, is that correct? --> Basically Out Of The Box only afford until 250 records, but this is for on demand workflow (because you select the records from view, which is, maximum is 250 records out of the box, then click the Run Workflow ribbon), but in this case you are using real time workflow and not on demand workflow."

You are using real time workflow, once the record is created or updated, or anything, based on the trigger, you do not need to worry about record limitation (250 records) since you are using real time workflow, not ondemand workflow, not manual workflow.

There are multiple ways to do that. You can store user email address in Account form in a field. When User lookup value gets changed at account, then update that field on account form using real time workflows.

1. On the Account form, create a field to capture the User's email address

2. Configure a Real-Time workflow on the Account form to populate the User's email address to this field.

3. Create a new field on the Opportunity form to capture the user's email address. Ensure the datatype and length of this field is the same as the one created on the Account entity

Open the relationship between Opportunity and Account [Potential Customer] and create a new mapping between the Opportunity User Email field and the Account User Email field.

The other option is to replace Step (3) above with a real-time workflow which runs upon create of the Opportunity record.This workflow will populate the Account [User Email] value to the Opportunity [User Email] field.

My suggestion you use a web resources to display User infor, including fullname, email, business unit, etc since Quick View Form only supports up to 1 level.

Because, if not, if you store the information at somewhere, let's say Account or Opportunity, you should maintain this.

For example: if the lookup field to user in the Account form has been changed, then should change the field at the Opportunity form level.

Then, if you store in the Account as well, you should maintain when create and update as well.

It is up to you.

If you don't want to use web resources, then, the easier way is by creating a workflow, set to Account, triggered once created and updated (if User lookup field in Account form updated), then update copy over the required fields from User to Account.

Then, assuming, you have all those required fields, you stored in the Account.

Thus, you can use creating a new Quick View Form of Account, then put in the Opportunity Form.

This is the sample of quick view form:

*assuming this is in the Opportunity Form, and the email is User email stored in the Account.

Using this method, you will only need to maintain fields in the Account once the lookup field to the User at the Account entity was updated.

If I run a realtime workflow, am I able to pull data for all records from the parent record to the child record?

--> Yes, you can, pull data from parent to the child record, by creating fields with the same data type.

I read somewhere that the workflow can only process 300 records at a time, is that correct? --> Basically Out Of The Box only afford until 250 records, but this is for on demand workflow (because you select the records from view, which is, maximum is 250 records out of the box, then click the Run Workflow ribbon), but in this case you are using real time workflow and not on demand workflow.